Plants as in underwater plants like anacharis and algae put oxygen in the
water during the day, due to photosynthesis, but at night they use oxygen.
The air stones, water falls, or other means of improving oxygen levels need
to be run during the night more than during the day. The quickest tell tale
of problems to come is the fish gasping at the surface first thing in the
morning. The next morning, or the next, you will find dead fish. If the
fish are gasping, put in a pint of hydrogen peroxide per thousand gallons,
and the fish should start to settle down in just a few minutes.
--
RichToyBox
http://www.geocities.com/richtoybox/pondintro.html


"jammer" wrote in message
...
Besides plants, is an air stone the only way to increase the oxygen?
This is the first full summer for the pond and it is HOT. Is there a
danger zone temp where water HAS to be cooled or air MUST be supplied?
I don't have electicity out there yet. I could run the trouble light
out there and throw in a small aquarium stone i have, but it would
have to be during the day when no one else was home.

This is a 60-70 gallon job and I have 2- 4 inch goldfish and about 30
toadlets.

Comments?